One of the benefits of using WF4 to create workflow is that it provides a graphical workflow designer. This means in most of the cases, developers don’t need to write code to define their workflows. Instead, they can use the graphical workflow designer...

Recently we've received a few customer feedbacks reporting WF4 workflow designer would have bad performance or hang in some cases even when the workflow is relatively small. We've worked with customers and found out that it was actually a WPF issue. ...

We talked about WF4 Activity overview and WF parameters in particular in previous posts. In this installment, I'm going to focus on WF variables.
Variable
Variables are modeled by Variable class.
namespace System.Activities
{
public abstract...

The WF State Machine Activity Pack CTP1 is released on CodePlex NOW!! Please check it out.
Last year in PDC2009, I ran a chalk talk on our work on WF 4 State Machine Activities and promised the team would ship an implementation for public review after...

We are happy to announce that we have released the WF ADO.NET Activity Pack CTP1 on CodePlex .
The WF ADO.NET Activity Pack CTP1 contains a set of WF 4 Activities based on .NET Framework Data Providers . These activities enable accessing a database...

In the 1st segment , I talked about high level principle for WF4’s data model design. I’m going to talk about WF Argument in particular in this post.
Argument
We’ve briefly touched this before: in WF4, arguments are modeled by Argument class...

In previous blogs , we went through how define an Activity’s execution logic. But this is not enough. To build any meaningful Activity, developers also need to the activity’s state and data flow. In this post, I’m going to talk about WF4’s Activity data...

Workflow Foundation Internals (III)
Andrew Au
Continue with our last article, we will work on allowing parallelism and create the workflow/host communication pattern. This pattern is actually very common, such as waiting for multiple approvers to...

Workflow Foundation Internals (II)
Andrew Au
Continue with our last article, we will work on separating program and data. Program and data are very distinct concepts from the perspective of a programmer. For example, you can run code, but you can...

Workflow Foundation Internals (I)
Andrew Au
Inspired by the book Essential Windows Workflow Foundation that describes the last version of Workflow Foundation, I can’t stop myself trying to write an equivalent piece for WF4. While the basic working...

In previous post I introduced WF 4's Activity model. In this section, I'm going to use 2 samples to demo 4 styles to create a custom Activity .
How to build a leaf activity – HttpGet
Today HTTP based RESTful services are getting popular, so it...

Workflow as Activities
If you have programmed with Windows Workflow Foundation (WF) , you should be very familiar with Activities . In WF , programs are defined by a tree of Activities . Some Activities are used to control the flow of program, like...

A new programming language Windows Workflow Foundation (WF) 4.0 offers many features to simplify business application development, deployment and management. In this post I’d like to explore workflow from a developer’s angle as a new programming language...

.NET 4.0 and WF 4.0 include a new event-driven control flow activity called Pick that takes the place of the original Listen activity in .NET 3.x. Whereas the branches in the Listen activity may be triggered only by activities that implement the IEventActivity...

In PDC this year, PDC2009 in Los Angeles, I got the chance to share with some of you on the future plan on State Machine in a chalk talk presentation, and did a demo of an early prototype with an Order Processing scenario. And I would like to thanks those...

Welcome to Go With The Flow blog, where we focus on all aspects of Windows Workflow Foundation (WF) in .NET Framework, including technologies , news and various events. Through this blog, we hope we can have more communication and interaction with all...